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Line Magnetic 845 Premium bias setting. Advice needed!

Hello everyone,

I recently got a used Line Magnetic 845 premium and I need some help with bias setting.

I am not entirely sure how to adjust the bias with the knobs in the front. 
I believe the correct bias setting is 70mA for the 845 tubes (V1-V2) and 45mA for the 300B tubes (V3-V4).

Here is a photo a small video to see how its setup at the moment:

https://app.photobucket.com/u/mpolyzos75/p/243cc263-f1e0-44b8-8191-30b26d923a30

https://app.photobucket.com/u/mpolyzos75/p/947469e5-f99d-445c-ab8c-d2a8d3aba496

Are the knobs set to the correct setting?

Any ideas are appreciated. 
Many thanks.
mika75

Showing 6 responses by mika75

mika75 OP
6 posts
 

Thank you very much facten.
mika75 OP
6 posts
 
The manual is very poor unfortunately. Thank you.
mika75 OP
6 posts
 
@facten 
Thank you for this. It doesn't explain clearly what the knobs on the front do though. Anyway its all sorted now. 
:-)
mika75 OP
6 posts
 
I know,it's crazy!
But the sound the amplifier makes is so good, makes me forget these things
mika75 OP
6 posts
 
Hello everyone,

Good news!

I emailed Jonathan Halpern from Tone Imports and Charlie Schnyder from Stereo Haven and they both promptly replied within an hour or two and they both said the same thing.
Apparently the knobs in the front are for fine tuning and not of much importance. The bias is adjusted mainly by the screws on the top for each tube. As long as the needles rest on the middle dot for each tube everything is ok.
This has been bugging me ever since I got the amp and I even emailed Line Magnetic in China and still the reply I got was far from useful.
These two guys put my mind at rest. Can't thank them enough!
:-)
mika75 OP
6 posts
 
@facten 
👍🏻
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